[Fire HD 8 and HD 10 Android Development] Selexo:
Changing DPI

So I have always found it useful to change the DPI on my phones. I usually like more text on my phone so I usually need to drop the DPI. But on this Amazon Fire HD 10 I found myself wanting to do the opposite because the screen density isn't very good for the size of the display (149 ppi is really crap for a screen this size) so the text looks worst than it should in some cases. In any case it really easy to change the DPI without root (adb), but you do require root to do local DPI playthings, but most of you should already be rooted by now. I use "Termux", tho you can use "Terminal Emulator for Android"

First you have to be rooted to do the commands locally, adb comes on the tablet but you can't adb locally, this is what a rooted "terminal emulator" does when you "su" locally, you get full control of your device minus all the adb clutter. (all the commands work in ADB, just add "adb shell" in front of most commands, or "su" in a "adb shell" alone). Cool thing is this tablet supports OTG so in fact you could adb from tablet into another device (power users), in case you didn't have a computer handy. Anyways, back on topic.

First launch your preferred terminal app and gain root access to your device using the command below.

su

The DPI of my 10 inch is 160 by default, and this can be found with this command

dumpsys display | grep mBaseDisplayInfo

I used 240 but change the RED to whatever you would like. I liked 200 but FWI* (below)

wm density [COLOR="Red"]240[/COLOR] && reboot

When your tablet is rebooted you will find that everything got bigger and easier to read. So did all the icons, so you may have to find your sweet spot. Lucky none of the amazon apps are DPI fixed so they don't crash or FC when I tried them. Of the ones I tried they all seem to scale the text and UI properly. Unlike my phone on stock, where if I changed the DPI half my system apps got missing icons, and most of them didn't launch lol. Thankfully the Amazon tablet seems to scale its DPI just fine and assuming you properly install the (nodpi) app store and services you should be fine. If you find a app that doesn't work anymore you may need to reinstall the app from the play store in case it downloaded a fixed DPI version of some game or app. Tho all my games seem to be running fine.

FWI: if you set your DPI too high you device may no longer be seen as a tablet to some apps, or maybe even the playstore, and may get some strange message saying can't run on this device, or the opposite. For instance "Google+" refuses to install from the playstore on a table even tho if you manually download the apk and install it, you will find that it works fine. Just "Google+" isn't officially supported so it won't even show up in the search and if you link to it it directly in the playstore it will show not supported with no download button.

While custom DPI's looks nice (180-200); look almost perfect on this 10 inch version. Google Play will start forking the RH-01 error if your in anything but the following DPI's below. And some apps are hardcoded to refuse to run in non standard DPI's. Just a forewarning.

Standard DPI's

160
240
320
480
640